Explosive engine



peb. Y C. A.'ROBERTSON, I

vExPLosIvE ENGINE Filed Nov. 14, 1921 3 Sheets-Shea?, ll

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MHH-70 c. A. ROBERTSON Feb. 5 9

EXPLOS IVE ENGINE 3 Sheets-Sheet 3 Filed Nov. 14 1921 Feb; 5.5f1924.

- C. A. ROBERTSON EXPLOSIVE ENGINE Filed Nov. 14, 1921-15l :s sheets-sham 3 Patented Fe 'if ED, STATES;

CHAnLnsA. nOBnn'rsoN, or srnINGrInLn, ILLINOIS, AssIG-Non To MONTGOMERY wenn av Co., INC., or CHICAeo, ILLINOIS, A CORPORATION orILLINoIs.

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Application led'November 14;,` 1921.

To all whom it may concern.'

Be it known that I, CHARLES A. ROBERT-` SON, a citizen of the United States, residing at Springfield, in the county of Sangamon and State of" Illinois, have invented certain new and useful Improvements;` in Explosive Engines, ofV which the following is a specification.

This invention relatesto internal combustion engines. It has to do particularly with engines of the four-cycle type, and resides in a new and improved construction and assembly ofy parts designed tosecure certain advantagesl rendering the engine particularly adapted to generalservicenses.

The general purpose of' the. invention` is the provision of an engine peculiarly adapted as a portable power generating unit which will fulfill the requirements of such a machine for general farm usage andthe like. As a consequence of this general purpose, it is one of the particular objects of the invention to provide an engine which comprises a minimum number of parts, and the operation and maintenance of'which are as simple as possible.

Another particular object ofthe invention is the provision of an internal combustion engine which is so constructed and` arranged as to eliminate vibration as completely as possible and at the same time afford a unit of minimum weight.

Another particular object of the invention is the provision of a constructionin which all of the operating parts are readily accessible.

Other and further objects ofthe invention will be pointed out hereinafter, indicated in the appended claims or obvious uponr an understanding of the present disclosure. In the drawings forming a part Of thisspeci- `ication, I show an. embodiment of the invention, but it is to be understood that the same is presentedV here for thefpurpose of illustration merely, and that the structure is susceptible of variation and modification within the scope Of the invention.

In the drawings,

Fig. 1 is a sideview of the operating parts, frame members for the most part being omitted, the cylinder, waterA jacket and exhaust valve chamber being shown in vertical section, and `the timing and.l ignition mechanisms in elevation Serial No. 515,174.

Fig. 2 is a detail in the nature of a side elevation of the cylinder head;

Fig. Bis a rear endview partly in elevation and partly in section Fig. L.Lis-fa front elevation; and

Fig, 5-` isa top viewshowing the frame, timingand throttle control mechanism, the cylinderw portions and crank casing being removed.`

By reference to these illustrations, it will bey understood thatthe .numeral 1 designates lateral frame members which may be formed most. conveniently of channel bar sections disposed, on edge. Adjacent their rearward extremities these frame members maybecennected by a spacer ortie-bar 2, while.V the lmain e connectionV between the lateralframe members `is afforded by the 'cylindery casting. This` is thel hollow,v casting shownvinelevation in Eig. 4 and in section in Fig. 1. I thas the` laterally extending bracket portions, 4 connected to the respective.frame,members` l by suitablel bolts 4f?. The cylinder. casting isof generalI rectangularform and comprises anfexternal jacket portion, withinlwhich andspacedv from the side and, bottom wallsV of which,`is formed a sleeve.. portion 6- which constitutes the cylinder proper. The space between the sleeve, and the housing affords circulating space for cooling water in contact with the outer wall of, the, former, and a top aperture 5a in the housing permits the introduction of the water thereinto. In the top portion of the sleeve 6 under the opening 5? is cast aboss 6? having a vertical channel communicating with the interior of the sleeve 6, on Whichpboss isseated an oil pipe 7 which` supports an oil cup 8 and afi'ordsa conduit, for conveying oil therefrom to the cylinder. TheV forward end 'of the vcylinder sleeve is closed by lthe cylinder head 9. This, is a casting formed with,l a lower bracket 10 upper braket or shelf 11'. the inlet valve,v housing 12, the exhaust valve housing 14; and the ignition plug seat 15. Bolts. 16. secure the cylinder head to the end wall of thev housing` 5.u Upon the inlet valve housing 1.2` is mounted thel carbureter 17, while, themuijlxier 18 is mounted on the. exhaust valve. housing and the ignition plug 19 is monnted on the" ignition plugs'eat 15. |Ifhe` inlet housing 1 2 aifordsf communication between the @abarataeill. the interior 0f the engine cylinder 6, while the exhaust valve housing 14 affords communication between the engine cylinder and the muitler 18. The shelf 11 supports the magneto20 and the associated ignition contact mechanism 21, from which the connection 22 leads to the ignition plug` 19. The arrangement is such that the cylinder 6 lies horizontally, the housing affording); a water chamber above it with circulating passages about it, and the cylinder head forming a support for the valve and ignition mechanism at the front end of the machine.

To the rear of the cylinder casting, the frame members 1 are provided with bearing lmembers 24 in which are journalledl the crank shaft portions 25 and 25a in alignment. These bearing members are secured to the frame members 1 by bolts 26. On its inwardly extending portion, the crank shaft `portion 25a carries inertia disk 27, while the crank shaft portion 25 has an outwardly extending portion carrying the pulley 2S, and an inwardly extending,` portion carrying inertia disk 29 and spur gear 30. lnertia disks 27 and 29 are, joined by an eccentrically disposed crank pin 31, from which the connecting rod 32 leads to the piston 34 which travels in the cylinder sleeve 6. Above-the wrist pin 35 the piston is provided with an oil channel 34n adapted to align with the channel in the boss 6a, while the connecting rod bearing 36 affords a drip cup4 36a disposed below the channel 34CL and connected by a channel 36') with the bore of the bearing member. The inertia disks 27 and 29 are formed with the counter-balancing portions B diametrically opposite the crank pin 31, the same being of proper weight to counterbalance the weight of the connecting rod and crank pin.l y

The timing mechanism includes the timing gear 37 which is carried on a sleeve 38 journalled on a post 39 which is mounted on one of the frame members 1. rlhe sleeve 38 carries a timing cam 40 and a disk 41 spaced therefrom. A timing' lever 42 is pinned to a stub shaft 44 which is journalled .in the lower bracket 10 of the cylinder head, one arm extending upwardly in to association with lthe ignition mechanism, and the other ,extending downwardly and supporting one t, end of the tappet rod 45. A spring 46 tends to swing the lower end of the timing lever rearwardly. The stub shaft 44 carries a tappet arm 47 supporting an adjustablelconi tact member 48 disposed for cooperation with theouter extremity ofthe stem of the eX- `haust valve `49, which valve is normally maintained seated by its spring- 50. The

rearward end of the tappet rod 45 is 4formed witha bifurcation 45Ll which rides on the sleeve 38 between the,` cam 40 vand the disk v41, and adjacent said bifurcation ca'rriesthe with the cam 40 under the influence of the spring 46. The ratio of the gear 30 to the timing gear 37 is as 1 to 2, and the form of the cam 40 is such that the tappet rod 45 is reciprocatedy once at each rotation of the timing; gear. rllhe upper arm of the ignition lever 42 carries a shoe 52 which is pivoted at 54 and designed tor cooperation with the operating-lever 21a of the ignition mechanism, so that upon forward movement of the upper arm ofthe ignition lever the dog will be rocked against the influence of its spring, the dog thereby escaping under the roller of the lever 21, while upon rearward Inovement, the rear end of the dog engages the lever A21a and rocks it rearwardly to the point where the roller escapes from the end of the dog, whereupon the lever is swung `forwardly byV its spring. This operation accomplishes the energization of the ignition plug-` to produce a spark in the customary fashion. The form of the timing,` cam 40 is such that the spark mechanism is oper- 'ated at the proper time, viz, at the start of the power stroke ot the piston, while the relationship of the contact member 48 to the stem of the valve 49 is such that the valve is opened at the end of the power stroke of 'the piston, and is held operi by the cam 40 during the exhaust stroke.

lln the operation of the engine, therefore, the operation of the ignition lever 42 by cam 40 fires the charge, the tappet arm 47 opens the exhaust valve at the end of the power stroke, and permits it to close under the influence of the springW 50 at Vthe end of the exhaust stroke, at which time the cam 40 has permitted the tappet rod 45 to move rearwardly, swinging the Contact member 48 away from the valve stein and the shoe 52 to a position in front of the lever 212. At the next stroke, which is the charging stroke, the exhaust valveis held seated by its spring 50, which spring is superior to the controllingl spring of the inlet valve. The latterconsequently is unseated by the suction, so that a charge is drawn from the carbureter into the cylinder. At the end of the charging stroke theinlet valve is seated by its spring and, the exhaust valve likewise being seated, the charge is compressed upon the return of the piston, and then tired as above described. A

I provide an automatic governing mechanism for controlling the throttle. Upon a cross yoke 55, which is connected at its ends with the lateral frame members 1, is supported a bracket 56 alfording a support for the governor. rlhe latter includes the inertia-elements 57 which are displaceable outwardly by centrifugal force, and the gov- ,ernor pinion 58 whichI is driven from the timing gear 37. Outward displacement of the inertia elements 57operates to retract the rod 59 which is connected to a bell crank lever 60 pivoted at 60a upon the yoke 55. The other arm of the lever 60 is connected to a rod 61 which has operative connection with a crank 62 which controls the position of the throttle valve 641, the swinging of the crank 62 rearwardly being effective to close the valve against the influence of its spring 65. Upon increase in speed of the engine, therefore, the inertia elements 57 will be projected, the rod 59 retracted, and the crank 62 swung rearwardly through the intermediation of lever 60 and rod 61, to close the throttle valve 64 to an extent determined by the speed at which the governor is being rotated. In this manner the supply of mixture to the engine is held under continuous and accurate control.

The fuel supply is carried in a flat tank 66 which is supported on the lower flanges of the frame members 1, with a filler spout 66u1 projecting at the rear, the liquid fuel being fed to the carbureter through a pipe 67. The timing and controlling gears, and other parts carried by the shafts 25 and 25a are housed by a lower casing 68 and an upper casing 69. rlhe pulley 28 is the medium through which the power is transmitted for the intended use. A ratchet connection 70 at the extremity of the shaft 25 alfords means for the attachment of a crank whereby the engine may be started. The engine is adapted to be mounted on a suitable running gear to facilitate its being moved from place to place. Suitable hanger brackets 71 may be connected to the frame members 1, affording support for a rear axle 72, while a front hanger 74C carrying a fifth wheel bearing 74P may provide a support for a front aXle carrier 75. y

An engine constructed as above described may be constructed very economically because it requires but very few parts, and

this feature contributes also to facilitate certainty of operation and ease of maintenance. Cooling is accomplished by convection through the water contained in the acket, the casting affording a reservoir of relatively large capacity facilitating cooling of the water at the surface. Lubricant conducted through the tube 7 is delivered to both the bearing surface of the piston and to the connecting rod bearing insuring in a very simple fashion the proper lubrication of these parts. Other bearings may be equipped with suitable oil cups or lubricant-receiving channels. The counter-balancing of the inertia members 27 and 29 and the connection thereof with the cylinder casting through the instrumentality of the frame members 1 minimize vibration. One advantage of the construction lies in the facility with which the mechanism may be disassembled. The entire valve and ignition mechanisms may be dcmounted as a unit by disconnecting the bolts 16 and uncoupling the tappet rod 45 from the lever 4-2. Likewse the cylinder casting may be removed by disconnecting the bolts la and the connecting rod coupling 31.

l claim:

1. ln a machine of the class described, the combination of a cylinder, a valve controlling communication to the same, ignition mechanism, a rocking lever, a piston operating in the cylinder, means for actuating said lever from said piston, and members operated through the instrumentality of said lever for operating the ignition mechanism and valve.

2. In a machine of the class described, the

CHARLES A. ROBERTSUN.

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